Modeling and simulation of the soybean oil meal desolventizing-toasting process

The desolventizer-toaster (DT) is an important plant equipment in the processing of soybean oil meal, its main purpose being the separation of hexane from the soybean oil meal. The DT must recover as much hexane as possible and produce a good nutritional quality meal with low energy consumption. The aim of this study is to develop a mathematical model for the DT to be used for optimization of operational conditions. The DT was modeled as a column with stages. For each stage complete mass and energy balances were considered, as well as thermodynamic equilibrium between the liquid and vapor phases. The equilibrium data were obtained from operational data of an actual plant. To check the suitability of the proposed model the behavior of the DT under different operating conditions was investigated: influence of hexane concentration of the cake on the meal moisture and the live steam consumption; the influence of the cake inlet temperature on live steam consumption; and the influence of the hexane content of the cake on the indirect steam consumption. (C) 2007 Elsevier Ltd. All rights reserved.